Work engaging device for screw machines and the like



May 15, 1934. Q LAUGHUN 1,958,828

WORK ENGAGING DEVICE -FOR SCREW MACHINES AND THE LIKE Filed Aug. 4, 1935 El mmc/nto?,

GUY AUGHL//V Patented May 15, 1934 UNITED STATES PATENT OFFICE WORK ENGAGING DEVICE FOR SCREW MACHINES AND THE LIKE 19 Claims.

This invention relates to work engaging devices especially adapted for use in bar forming maclL'nes, automatic and hand operated screw machines and other machines in which pieces of stock are held in position or rotated while being operated on by appropriate tools.

In the feed fingers and collets in automatic and hand operated screw machines and other` machines in which bars of stock are handled for presentation to cutting, threading and other tools, the tubular bodies of such feeders and collets are provided with spaced slots opening out through the ends of the bodies to define fingers for pressure relation with the work and such slots extend longitudinally of the tubular body with the result that there is a tendency for chips, oil and scale to collect therein and possibly work between the fingers and the stock and it is recognized by those skilled in this art that this is to be avoided if the machine is to be operated with maximum efficiency.

In looking to the elimination of this situation, I have provided a work engaging means of the class suggested in which the slots in the tubular body thereof extend at an angle negative to the direction of rotation of the body with the result that such slots are maintained substantially free of accumulations that might interfere with the operation of the machine, such accumulation being thrown outward and rearward, it being noted in this connection that the angle of the slots allows centrifugal force to assert itself to bring about the movement of oil, chips, and scale away from the point of engagement of the work engaging means with the stock.

The invention further contemplates a novel mounting for the pads of a feed finger, which mounting allows of the installation and removal of the pads without extensive spreading of the fingers, the arrangement being such that limited shifting of the pads is allowed so that the pads may adapt themselves to irregularities in the stock being handled.

Other objects and advantages will be apparent during the course of the following description.

In the accompanying drawing, forming a part of this application and in which like numerals are employed to designate like parts throughout the same,

Figure 1 is a sectional perspective illustrating the invention,

Figure 2 is a sectional perspective illustrating a master feeder embodied in the invention,

Figure 3 is a detail longitudinal sectional View through the master feeder,

Figure 4 is a perspective of the pad forming a part of the invention,

Figure 5 is a fragmentary sectional perspective illustrating the manner in which the pad may be mounted in the master without extensive spreading of the fingers. l

In the drawing, the numeral 5 generally designates a tubular body which may be formed from pressed metal, tubing, cast metal, or machined from solid stock. The body 5 has suitable attach- 65 ing means 6 internally or externally threaded, depending of course, on the nature of the mating attaching member 7.

By reference to Figures 1 and 2 it will be seen that the tubular body 5 is provided with a plu- 70 rality of spaced slots 8 opening out through the forward end of the body and defining transversely curved spring leaves or lingers 1U. v

As shown in Figure 2, the forward end portions of the fingers 10 are extended inward to define 75 strengthening and attaching shoulders 12 of arcuate formation, such shoulders being located in advance of and parallel to arcuate shoulders 14 formed on the inner sides of the fingers. More particularly, the shoulders 12 and 14 are located 80 in substantially spaced parallel relation and cooperate with the intervening portions of the fingers in defining seats for the reception of pads 16.

The rear shoulders 14 are shown to be grooved between the ends thereof and for the full depth and width thereof Vto define recesses or notches 1'7 for the detachable reception of lugs 18 formed at the rear ends of the pads 16. It Will be seen that the outer surfaces of the lugs 18 are flush with the outer surfaces or perimeters of the pads 16 and bear flatly against the inner surfaces of the fingers allowing the pads to fit snugly in place between the shoulders l2 and 14 and flatly against the inner surfaces of the fingers.

It is important to observe that the width and radial dimensions ofthe lugs 18 are slightly less than the corresponding dimensions of `the recesses 1'7 with the result that the pads may partake of limited movement with respect to the iingers. This allows the pads to adapt themselves in inequalities in the stock being handled.

Of course, the radial dimensions of the pads 16 are slightly greater than the similar dimensions of the shoulders 12 and 14 so that the pads may have pressure engagement with the bar of stock without interference by the shoulders.

It is shown in Figures 1, 3 and 4, that the pads 16 are increased in circumferential measurement toward points between the ends thereof and that the longitudinal edge portions of the pads protrude beyond the longitudinal edges of the fingers thereby defining opposed lands in the form of substantially equi-lateral triangles, said lands having apexes in engagement with each other to aid in securing the pads in place. Such lands are freely grindable to diminish the bore of the body. By this arrangement, it is a simple matter to compensate for wear on the pads by grinding the protruding portions of the pads to the proper extent.

The attaching means for the pads embodying the spaced transverse arcuate shoulders l2 and 14 and the intertting connections 17-18 provide a simple and quick means by which the pads may be installed without extensive spreading of the lingers and this particular structure has been found to be more economical to manufacture than radial pin and socket connections such as are found in other feeders.

It is important to observe that the angled or slanting edges of the pads cooperate with the connections 17 and 18 in providing for the simple and convenient application and removal of the pads without extensive spreading or separation of the fingers. In explaining this, it is pointed out that the pads are diminished in circumferential measurement toward opposite ends thereof from central points so that during application of the pads and until the pads are fully in place as suggested in Figure 3, the oppositely angled edges of the pads are flatly in contact with each other necessitating little spreading of the several leaves or fingers 10 to permit of substantially endwise movement of the pads. Thus, the angled edges of the pads act in concert with the lug and recess arrangement in facilitating the application and removal of the pads.

As brought out in the opening paragraphs of 1 this specification, one of the principal attributes of the invention resides in the means by which the slots 8 are rendered more or less self-cleansing. In this connection, attention is directed to figures l and 2 in which it is illustrated that the slots are of helical or spiral form and extend at an angle negative to the direction of rotation 'of the body 5 so that accumulations of chips,

scale and oil in the slots are thrown rearward and outward away from the pads and away from the stock. This avoids the possibility of particles of oil, scale or chips working in between the pads and the stock and possibly interfering with the eflicient operation of the machine. The negative angles of the slots 8 allow centrifugal force to assert itself with the result that the slots are maintained comparatively free of accumulations of the kind mentioned.

In further adverting to the slots 8 it is pointed out that the same open out through what might be said to be the forward end of the feeder and that such slots recede toward the other or closed ends thereof and in the direction opposite the direction of rotation of the body and also in a direction away from the pads. Thus, the'particles of oil, chips and scale, that would otherwise accumulate in the slots and possibly work in between the pads and the stock are directed rearward and outward, maintaining the slots free.

The collet 6G shown in Figure 1 is in the nature of a tubular body having a plurality of slots 62 opening out through the forward end of the collet and being of helical form having angles negative to the direction of rotation of the collet with the result that, as described in connection with the feeder slots, the collet slots are rendered self-cleansing to a high degree.

It is clear that the negative angle of the slots may be incorporated in a work engaging device with or without detachable pads.

Having thus described the invention what is claimed is:

1. In a structure of the class described, a tubular body having a plurality of slots opening out through one end thereof thereby defining a plurality of transversely curved fingers, said fingers being provided with inwardly projecting circumferentially extending front and rear shoulders, and pads between said shoulders and having rearwardly projecting lugs, said rear shoulders being provided between the ends thereof with recesses receiving said lugs.

2. In a structure of the class described, a work engaging member comprising a tubular body having a plurality of slots opening out through one end thereof thereby defining a plurality of transversely curved fingers, said fingers being provided with spaced, substantially parallel, circumferentially extending internal shoulders, one of said shoulders being provided between the ends thereof with a recess for the full depth of that shoulder, and pads between said shoulders, one of said pads being provided between the longitudinal edges thereof and at one end thereof with a lug received in said recess.

3. In a structure of the class described, a work engaging member comprising a tubular body having fingers provided with spaced, substantially parallel, circumferentially extending internal shoulders, one of said shoulders being provided between the ends thereof with a recess for the full depth of that shoulder, and lpads between said shoulders, one of said pads being provided between the longitudinal edges thereof with a rearwardly projecting lug received in said recess, said lug being of less depth and width than the depth and width of said recess.

4. In a feed finger for automatic screw machines, a tubular body provided with fingers having inwardly projecting arcuate circumferentially extending shoulders, one of said shoulders embodying a pair of spaced sections defining an intervening recess, and pads between said lshoulders, one of said pads being provided with a rearwardly projecting shoulder freely received in lsaid recess and movable endvvise into said recess.

5. In a work engaging member for automatic screw machines, a stock engaging rotatable tubular body having a plurality of clearance slots opening out through one end of the body thereby defining fingers, said slots being advanced toward the open ends thereof in the direction ofrotation of the body thereby causing chips within the tubular body to move outward in the direction of the other ends of the slots.

6. In a structure of the class described, a rotatable tubular body having a plurality of slots opening out through one end thereof to dene fingers and receding toward the other ends thereof and in the direction opposite the direction of rotation of the body, and pads'carried by said fingers at points removed from the receding portions of said slots.

7. In a structure of the class described, a tubular body having a plurality of slots opening out through one end thereof to define fingers, said lingers being provided with inwardly projecting circumferentially extending arcuate shoulders, one of said shoulders being provided with a recess opening out through one side thereof, and pads engaged by said shoulders, one of said pads being formed with a lug movable endwise into said recess, said pads being reduced in circumferential measurement toward the ends thereof to define protruding lands normally in contact with each other and defining inclined edges allowing substantially endwise movement of the lug into and out of said recess. Y

8. In a feed finger for automatic screw machines, a tubular body having a plurality of fingers, said fingers being provided with inwardly projecting front and rear shoulders, said rear shoulders being provided between the ends thereof with longitudinally extending recesses, and pads having the rear portions thereof provided with rearwardly projecting lugs movable substantially endwise into said recesses, said pads being diminished in circumferential measurement toward the ends thereof defining protruding lands having angled edges allowing substantially endwise movement of the pads with respect to each other for the introduction and removal of the lugs of the pads into and from said recesses.

9. In a feed finger, a tubular body having a plurality of fingers formed with inwardly projecting shoulders, and pads detachably located between said shoulders, there being a freely separable interiitting lug and recess connection between one of the pads and one of the shoulders and being entirely within the axial plane of that pad allowing substantially endwise movement of that pad during installation or removal.

l0. In a feed finger, a tubular body having a plurality of fingers formed with inwardly projecting shoulders, and pads detachably located between said shoulders, there being a freely separable interiitting lug and recess connection between one of the pads and one of the shoulders and being entirely within the axial plane of that pad allowing substantially endwise movement of that pad during installation and removal, said pads being formed with oppositely inclined edges defining bearing lands and facilitating introduction and removal of the pads.

l1. In a stock engaging device for screw machines, a rotatable tubular body having a plurality of slots defining fingers, said fingers being provided with internal shoulders, one of the shoulders being provided with a recess, and pads detachably mounted between said shoulders, one of said pads being provided with a lug detachably received in said recess and extending substantially parallel to the longitudinal axis of the tubular body.

12. In a work engaging device for screw machines, a rotatable tubular body having a plurality of fingers provided with pad restraining shoulders, pads between the shoulders and reduced in width in the direction of the rear portions thereof thereby facilitating endwise movement of the pads with respect to each other during installation and removal of the pads, one of said shoulders and one of said pads being provided with an interlocking lug and recess connection.

13. In a stock engaging device for screw machines, a tubular body having a plurality of fingers provided with internal shoulders, pads between the shoulders and reduced in width in the direction of the rear portions thereof thereby facilitating endwise movement of the pads with respect to each other for removal and installation of the pads, there being a longitudinally separable interlocking lug and recess connection between one of the pads and one of the shoulders and being entirely within the axial plane of that pad for substantially endwise movement of that pad during installation and removal of the same.

14. In a work engaging device for screw machines, a tubular body having a plurality of fingers provided with pad restraining shoulders, pads between the shoulders and reduced in width in the direction of the forward portions thereof thereby facilitating endwise movement of the pads with respect to each other, one of the shoulders and one of the pads being provided with a freely separable lug and recess connection.

15. In a work engaging device for screw machines, a tubular body having a plurality of fingers provided with internal pad restraining shoulders, pads between the shoulders and reduced in width in the direction of the forward portions thereof thereby facilitating endwise movement of the pads with respect to each other, one of the shoulders and one of the pads being provided with a freely separable interlocking lug and recess connection entirely within the axial plane of that pad allowing substantially endwise movement of the lug into and out of the recess.

16. In a stock engaging device for screw machines, a rotatable stock encircling tubular body having slots defining fingers, said fingers being provided on the inner sides thereof with stock engaging means, the slots in the said body being spiralled in the region of the said stock engaging means in the direction opposite the direction of rotation of the body for the passage of loose matter outward and away from the stock engaging means of the fingers.

17. In a stock engaging device for screw machines, a rotatable stock encircling tubular body having a plurality of fingers provided with detachable pads, there being clearance slots between said fingers and between said pads and 120 extending rearwardly and helically beyond said pads in the direction opposite the direction of rotation of the body for the clearance of loose matter outward and away from the pads.

18. In a stock engaging device for screw ma- 125 chines, a rotatable stock encircling tubular body having a plurality of fingers provided on the inner sides thereof with work engaging means, there being clearance slots between said fingers and between the work engaging means thereof 130 extending rearwardly and helically beyond said work engaging means in the direction opposite the direction of rotation of the body for the clearance of loose matter outward and rearward of the stock engaging means of the fingers.

19. In a stock engaging device for screw machines, a tubular rotatable stock embracing body having a plurality of slots opening out through one end thereof to define fingers and receding toward the other ends thereof in the direction opposite the direction of rotation of the body for the clearance of loose matter, said fingers being provided with stock engaging means.

GUY LAUGHLIN. 

